There are known detector-equipped gripping forceps that are provided with a cavity in the back side of a gripping surface and that detect a gripping force by using a strain sensor embedded in the cavity (for example, refer to PTL 1).
In the gripping forceps of PTL 1, wiring connected to the strain sensor is led out of the cavity portion at the back side of the gripping surface, and the wiring led out of the cavity portion is guided to the proximal-end side of a treatment tool in the form of free-space wiring.